Why doesnt my textview show up when I add autolayout constraints? - ios

I have a view which contains a textview (which displays a question) at the top. And 4 labels (for various answer options) with a stack of option buttons at the foot.
When leave the 'question' textview without constraints it appears fine in portrait. When I rotate the handset the text doesnt expand across the width of the screen.
I thought the way to resolve this was to click the add constraints pin/align button and click the T bars adding '0' constraints for top trailing and leading.
However when I do that the textview doesn't display at all. Any idea why?

The height constraint is missing. When you don't provide any constraints to your UITextView Xcode automatically will add the constraint's but as soon as you try to pin the top, leading and trailing anchors Xcode will not add any constraint's automatically.
You have to pin the bottom anchor of the UITextView to any of your buttons or give it a height constraint will solve your problem. Because UITextView will not calculate it's height based on it's inner content size like UILabel or UITextField.
If you want to only display some text and no edit functionality then you can use a UILabel and set the number of lines to 0.

Related

Move element when UITextView expands

I am trying to make a TextView in my scrollview look like the "Hoshi" TextField in this github repo raulriera TextFieldEffects
If I only have a textview with top/left/right constraint it will expand when I enter more text which is right.
But when I add a UIView under it, it will cut off the text if I enter alot of characters, what I want to do is to move the view/line under it along with the textview when it expands.
My constrains for the UIView is top space to textview >= 10 I thought that would move the View when the textview expands but nothing happens, instead the text gets cut off and the view wont move
Here is a image for the constraint:
So how can I make the view move once the textview expands?
Programmatically change the height constraint of the textview based on the text entered.
Remove the bottom constraints of the lable it will work as desired.That bottom constraints don't allow your lable to move down as your textView height increases.
I found a solution.
I had to set the UIView's bottom constraint to be >= low priority (250). That would make it expand together with the textview

Xcode IB auto sizing?

Everything looks fine in IB. When I run my app using an iPhone5/iPhone6/iPad sims, it's completely mangled.
In IB:
In iPhone6 sim:
In the above sim, the buttons are cut. The textfield and textview are also cut. For the TF & TV, they are aligned center but trail off the edges on both sides.
I have the buttons width set
Editor > Pin > Widths Equally
The title label is set with a
Horizontal Center in Container
constraint
The textfield and textview also have
Horizontal Center in Container
and
Editor > Pin > Width
Is there some way to fix this?
-- EDIT --
After a few tries with constraints, looks like I have everything working except the two buttons.
Current listing of constraints:
As suggested by others, you should consider using the Auto-layout feature if you plan on constructing your views using the IB.
Here are some tutorial links:
RayWenderlich.com Part One
Youtube video This one covers a bit of size clases
Hope they help.
UPDATED:
I've read your updated post, you need to add width and height constraints. The view you see in the IB right now is 600 by 600 points, and the simulator one is smaller, which means that if you leave it as is, when you run the app you'll only see what the iphone screen has the capacity to show.
You need to add more constraints than what you used, try defining an equal width for the buttons, and assign the left one a left margin constraint, the right one a right margin constraint, give both of them vertical spacing constraint related to the text view or long label, the text view or long label should have left and right margin constraints, a height constraint and a top constraint to the textfield, the textfield should have a vertical spacing constraint to the label, also left and right and height constraint, and last the label should have leff, right and height constraints plus a top constraint to the main view.
I feel that those are all you need, but Xcode will through warnings at you if it feels you are missing something.
Try it, and let us know.

Swift - UIScrollView Scrolls Partially

My problem is slightly different from other's 'Swift UIScrollView' problems when using auto layout:
Problem:
Unlike others, when I run my app, it scrolls. My problem is that the scroll cuts off the bottom 20-30% of the content. I can pull to see the buttons did build and are down there, but when I let it go the scroll snaps back to a false bottom which cuts off my content!!! I've been trying, for days, to fix it to scroll the entire height but it continues to cut off!!
Description of app:
I used auto layout to layout 6 buttons and labels. Each button a rectangular image, with a label directly beneath it. (sorry, the site won't let me post pictures!)
I have my views arranged like this:
MainView > ScrollView > ContentView > Buttons & Labels
I have my contentView pinned to my ScrollView and my ScrollView pinned to my MainView. My buttons and labels all have constraints that are building correctly, to create a list that looks like:
Rectangular button
Label beneath it
Spacing
Rectangular button
Label beneath it
Spacing
Etc.
Can anyone tell me why I can't scroll the full length of the view?
Your description of how your items are constrained is vague, so I'm going to list all of the constraints you need to make this work. Then you can compare what you have to what you need and adjust accordingly.
Your ScrollView should be pinned on all 4 sides to the MainView. (This isn't absolutely necessary. You can constrain your ScrollView however you want, but make sure it can grow as the device and/or orientation changes).
Your ContentView should be pinned on all 4 sides to the ScrollView with offsets of 0.
Since you want your ScrollView to scroll vertically only, constrain the width of the ContentView to the width of the ScrollView using an Equal Widths constraint. To do this, in the Document Outline view, Control-drag from your ContentView to your ScrollView and select Equal Widths from the pop up.
The height of ContentView will be set by the sum total height of everything in it. In order for this to work, your topmost button needs to be pinned to the top of the ContentView, all of your buttons and labels should be pinned to their nearest neighbors, and the bottommost label should be pinned to the bottom of the ContentView. In addition, all of your buttons and labels should have constraints for their widths and heights. I would suggest setting an explicit width constraint and explicit height constraint for your buttons and centering them horizontally in the ContentView. For your labels, set an explicit height constraint and pin the left and right edges to the ContentView.
If you have these constraints and no other ones, your ContentView will be properly sized.
Using contentView, like you said, usually fixes the issue. So chances are you need to take a second look at your contraints. Maybe try this solution in a clean/new project to see that it works. (it does work). My guess would be that some of your constraints conflict each other.
Otherwise I think it would be a good idea to setContentSize of your scrollView in your viewDidLoad.
Another hack would be to place 2 UI objects with their alphas set to zero on the right top corner and left bottom corner. This would hint scrollView to set its contentSize.

How to change uiview's height using auto layout?

So I created this scenario in order to understand how views increase in height according to their content. However am still not able to make it happen.
This is what I have now:
the textview is growing according to content. however the uiview containing it is disappearing. what constraints should I use so that when the uitextview becomes bigger, its parent view also increase in height?
Start by clearing all your constraints from everything so we have a fresh slate.
Step 1: Build your view hierarchy. In this example, we want something like this:
The view controller's view, which we'll call parentView has a subview, which we'll call redView. That redView has a child, a Text Field, which we'll call textField.
The hierarchy looks like this:
Step 2: Set any constraints that are specific to any individual view. In this case, we probably only want to set a width constraint on our text view. For now, I'll just set a width of 200pts.
Step 3: Set the constraints between textView and its parent, redView. Let's say we want a 10pt border all the way around. Let's add these constraints:
Once we've added these constraints we'll gets some auto layout warnings and errors. For starters, because the constraints I added for with and space to superview don't match the actual sizes, I'll get some warnings like this:
There will also be some errors describing missing X and Y positions for redView and for textView. There are really twice as many errors here as necessary. textView knows where to position itself relative to redView. We don't need more constraints to sort out textView's position. However, redView doesn't know where to position itself yet... and so ultimately, textView also sort of doesn't exactly know.
We can update the textView's frame to get rid of the warnings, but let's go ahead and fix the actual errors.
Step 5: Set up redView's constraints relative to the superView. redView already know what size to be. Notice we had no errors for redView's width. It just doesn't know where to be. In this case, I'll go simple and say we want redView to be centered. So we'll want to add these constraints:
Now we've fixed some of the problems. The only problem that remains is the height for everything.
To fix this, we must set the content sizing priorities of textView. Set these all to 1000 and change the "Intrinsic Size" property to "Placeholder".
By now, all of the auto layout errors should be gone and we should only be left with warnings because our storyboard frames don't match what our constraints say they should.
We can fix that by selecting parentView and updating all the frames:
There's one final caveat to this auto layout puzzle when it comes to autosizing based on content size: what happens if our text view has no content?
If our textview has no content, auto layout will choose a height of 0, and our users won't even be able to see that there's a text view there, much less tap in it to add content (and make it expand). When using auto layout and content-based sizing, we should almost always be sure that we've set either an explicit or minimum size for the content view.
We don't have to worry about our textView's width, as we set this explicitly to 200. So let's add a minimum height constraint. Start by adding any height constraint:
Now go to the size inspector for the textView, find this height constraint we added, and edit it into a greater than or equal to constraint:
Storyboard won't reflect the change in content in our textView and resize it appropriately, but your constraints are now set up correctly and this will behave appropriately on your device or in the simulator.
ON UITextView make your you unselected These
Scrolling Enabled
Bounces
Bounce Horizontally
Bounce Vertically
Shows Horizontal Indicator
Shows vertical indicator
Now Change your auto layout constraints like this.
On the Storyboard Page, click on your textview.
Then click on the small triangular in the lower right corner.
Click first on "Clear Constraints".
An then on "Add Missing Constraints".
Its the easiest way.

Adding UIButton to custom cell with auto layout

I am trying to add a button through IB in a custom cell at top right corner of the cell. I am using auto layout to position it correctly but in simulator I don't know why the button wont show up.
But if i create it programmatically then it shows up perfectly.
So my question is how can achieve it using IB and where i am doing it wrong.
I have added four constraints on my button leading and trailing space to superview and fix width and height.
Remove leading space constrain and add fix to top space constrain. I mean there will be total 4 constrains Fixed width, height and fixed trailing, top space to super view and it will work. If it is not working means you have not set your tableView constrains. For tableView fix it from top,bottom,left and right space from super view.

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